Crossover homogenizing apparatus



Feb. 5, 1952 J. BAILEY CRO SSOVER HOMOGENIZING APPARATUS Filed March 7, 1947 w oo 5 SD eeeeo 8, oo oeo /0 ege'oo l e f INVENTOR BAILEY BYW, +7510@ JAMLS ATTORN EYS Patented Feb. 5, 1952 y CROSSOVER HOMOGENIZING APPARATUS James Bailey, West Hartford, Conn., assignor to Plax Corporation, Hartford, Conn., a corporai tion of Delaware Application March 7, 1947, Serial No. 733,170

Claims.

The present invention relates generally to the manufacture of plastic articles, and has for a principal object the provision of novel appartus by means of which a confined stream of more or less heterogeneous plastic material may be thoroughly mixed before the material is shaped to a desired permanent form as, for example, by extrusion through a die in the form of rod or tubing.

Apparatus embodying the invention operates to nely divide and thereafter reunite a stream in a novel manner characterized by the fact that the reunited stream is turned inside-out and outside-in and rendered considerably more homogeneous than the original.

One embodiment of the invention is illustrated in the attached drawings, in which:

Fig. 1 is a cross-sectional elevation of an homogenizer including a pair of members oriented relative to each other for receiving a stream of plastic, as from an extruder, and successively dividing, distributing and reuniting the stream prior to delivering it to a forming die;

Fig. 2 is a perspective view of one of the pair of dividing and distributing members shown in Fig. 1; and

Fig. 3 is a cross-sectional view taken through line 3-3 of Fig. 2 of the novel dividing and distributing member,

Referring more particularly to the drawings, there is illustrated an homogenizer including a three-part housing, indicated generally by the numeral l, the components of which are designated by the numerals 2, 3 and 4. The housing I is generally cylindrical in shape and denes a continuous cylindrical bore 5 which is connected in a plastic supply line intermediate an eXtruder 6 and a forming die 'l as by means of threaded couplings. Only the outlet end of the extrudery 6 is illustrated in the drawings, it being understood that the details of the extruder are not material to the invention and that a variety of commercial models may be employed' to supply a plastic streamthrough the homogenizer to the die 1. Likewise, the type of die employed may vary, the one shown being merely illustrative of a forming member or die generally. Plastic from the extruder 6 is received by a smaller diameter upstream portion 5a of the main bore 5 and channeled through-the larger main ybore 5 and then through a smaller downstream bore 5b to the forming die 1.

Disposed/in the passageway 5 are a pair of like dividing and distributing elements which, while identical in structure and identied, generally,

by the common numeral 8, are, for more ready reference, distinguished in Fig.l of the drawings by diierentiating reference letters, theupstream element bein'g identied as 8a and the downstream element as 8b. Inasmuch as the construction of thev two elements are` identical, their several component portions are identified hereinafter by the same numerals,- distinguishing letters being added in those instances where, for clarity, it is desirable to distinguish between like portions of the two elements.

Referring more particularlyto the construction of the like elements 8a andb, each comprises a steel member having a generally cubical body portion 9 and an integral circular supporting frame portionv l0 which divides-the body portion 9 along a diagonal so that like wedge shaped portions Il and l2 are located vonopposite sides of frame I0. Each wedge includes a pair of plastic distributing surfaces I3 and i4 which are disposed at 45 angles to the support Il and at to each other, and which intersect to form a plastic separating or dividing edge generally designated by the numeral l5. When assembled in the homogenizer, the circular support I0 of the upstream die member 8a is secured between the opposing surfaces of the members 2 and 3which are cylindrically recessed at 2a andn3a so as to center the circular'mernber Ill relative to the cylindrical bore 5. The members 2 and 3 vare also milled at 2b and 3b so as to receive, respectively, the identical upstream and downstream wedge portions Il and l2 of the distributing member 8a. .Y A

Similarly, the cylindrical support Ill of the downstream dividing and distributing member 8b is centered and secured within the cylindrical recesses 3c and 4c which are formed in the adjacent surfaces of the housing components 3 and 4. In addition, the housing components 3 and 4 are suitably milled to receive the upstream and downstream wedge portions Il and I2 of the downstream distributing member 8b.

As shown in Fig. 1, the housing component 3 receives and Orients the upstream wedge portion Il of member 8b at 90 to the downstream wedge portion l2 of the upstream distributing member 8a located in the milled recess 3b. Thus, where the upstream dividing edge I5a of the wedge 8a is disposed transversely of thebore 5 along a hori- Zontal diameter, the corresponding upsteam dividing edge l5b of the downstream distributing member 8b is disposed transversely of the bore 5 along a vertical diameter.

As illustrated in the drawings, a seriesof distributor ducts or channels I6 extend through each distributing member 8. The channels I6 are arranged in spaced planes which are both parallel and normal to the surfaces I3 and I4. More particularly, the series of channels are alternately staggered so that at one level, parallel, equally-spaced channels I6 extend through the distributing member 8.normal' to the 'surface I3 and parallel `to thesurface I4,'"and vthe next spaced series of channels extend through member 8, normal to the surface I4, and parallel to the surface I3.

The location of these channels is best described by the manner in which 'they function. Plastic material, which is forced ina continuous lstream by the extruder 6 into the homogenizer inlet 5a. is divided by the edge I5a of the .upstream .dividing member 8a into like upper and lower components in the bore 5. The upper component, in part, slides along the distributing surface I3, a -portion, .fat least, beingiforced'through :the :channels :.or :duets I6 Ln'earest vthe dividing fedge I5a. .Those channelszreceive `plasticxfrom the center of the stream andldirectzit'to the outer wall orconiinesof the passageway V5 downstream of the distributing 'memben 'Whereas plastic from the zoneintermediate'the vdividing edge I5a and the `upperwallof the bore '5 is received, 'at least :in part, by theducts located. centrally of 'the wall I3 rand. isfdistributed 'downstream to points intermediatethe `center, line vand .the'lower wall 'of theibore 5. 'Finally, the `plasticrilowing valong the upperrwallof'theborei5,land1that portionwhich slidesfalongV the Wall I3 and does not `enter the :intermediate ducts, enters the series of ducts, which are parallel to and most'l remote from wall I4, and is discharged `downstream adjacent to kand just beneath the center of the bore y'5.

Similarly, the :ducts I6, 4which open into the lower dividing faceM, transpose, 'at least in part, the components 'of the 'lower half 'of the stream of plastic relative to the reenter line and .lower wall of the bore 5 and discharge the :plastic Adownstream in the transposed order in :the .upper portion of the boi-c55. Y

The 'ducts Ir'in'lth'eeupstream dividingam'ember 8a thus act -to .'at "least partially "itransposey the components Aof the upper-rand lower portions divided 'from the mainstream 4by the upstream dividing edge I5a. Atthe'same time,1the central portion `of :the main "stream :is Idistributed, at least in part, to the `'outsideu'oi .the stream and the outside of the main streamisidistributed, .at least lin part, -tothercenterof thefduct 5. Thus. when the'several components ofthe plastic stream are reunitedatthe downstreamfsideofithe dividing member 8a, the .'stream,"at least in part. has been turned inside-'out"and-foutsidin, .as well as up-portion-down and `downeportion-up, with respect 'to dividingedge -I5a.

It will be understood that plastic, upon reaching a dividing'wall vsurface lf3 or I4, is not all immediately :received-by the nearest channel I6 inletfand that-portions ofthe stream slide along the vwalls I'3fand I4; and `are received by channel flopenings locatedinearer the Aouter confines of the bore 5 tand downstream loi ltherpoint where :the plastic originally reached the surfaces I3 and I4. The 'reunited `stream of plasticy material Vintermediate .the distributing members 8a and Bb, is

'again turned"inside-out^by the member 48b and, further, transposed. about .a l,vertical .rather than a horizontal axis. Inithis'connection, thefverti- `cally disposed dividing-:edge I 5brandxthedirecting walls I3 and I4 act to divide the reunited stream into equal fore and aft components and the distributing channels I6 act to transpose the plastic material hind-side-to in the reunited stream which is delivered by the homogenizer outlet 5b to the die or forming member 1.

It will be seen that the present invention acts .'tofreceive. and thoroughlymix a 'streamof plastic 4and to discharge it in'a more thoroughly homoi geneous condition than that in which it may -have been received. The stream, at least in part, .in turned up-sidefdown, and hind-side-to,` as

well as inside-out.

The embodimentlof the invention illustrated is -readilyassembled and disassembled, a single set of -bolts I'I being suilcient to hold the several parts 2, .3 .andA of the housing together with the distributing members 8a and 8b properly lo- -cated in assembled position.

Where thermo-plastics are passed through the 'homogenizen thetemperature may be readily .controlled by means of a heating coil I8 located Aabout the peripheryof thehousing.

terial constituting va connedrplastic streamflowing continuously under pressure including a housing for laterally confining the flow of plastic material therethrough, axrst distributing member for dividing the stream along a first line through approximately yits `center into two substantially equal parts,'a vplurality :of channels in said distributing member for vdirecting plastic from one side of the dividing line'to the other into a reunited stream in the housing, a second distributing member forredividing the stream along a second line through approximately the center of said reunited stream Vinto substantially equal parts, said'rst and second Vdividing lines being at approximately right angles to the stream and to each other, and a plurality of channels in said distributing member .for directing Vplastic from each part-of thevredivided'stream `from one side of the second dividing line to the other into a reunited stream.

2. Apparatus'formixing plastic material including a housingI for laterally confining the flow of plastic material therethrough, a rst distributing member for dividing the stream along a first longitudinal plane therethrough, a plurality of channels in said distributing member for directing material from vone side of said plane to the oth-er into a reunited stream in the housing, a second distributingmemberfor redividing the stream along a second longitudinal plane, said first and second longitudinal planes being angu- .larly disposed to each other, and a plurality of stantiallyequal parts, aplurality of channels in said distributing'member for .directing portions substanti lly equ parts, said rst and second dividi bi/lg at approximately right angle'st am and to each other, and a plurality annels in said second distributing r directing portions from each part of theme/divided stream from one side of the second (dividing line to the other into a reunited Estr am.

4. Apparatus for mixing plastic material including a housing for laterally confining the flow of a stream of plastic material therethrough, a first distributing member in side housing for dividing the stream along a first line through approximately its center into two substantially equal parts, two sets of parallel channels in said distributing member, each set being angularly disposed to the other and to the stream of plastic material, for directing portions from one side of the dividing line to the other into a reunited stream in the housing, a second distributing member for r-edividing the stream along a second line through approximately the center of said reunited stream into substantially equal parts, said first and second dividing lines being at approximately right angles to the stream and to each other, and two sets of parallel channels in said second distributing member disposed substantially as in said rst member for directing portions from each part of the redivided stream from one side of the second dividing line to the other into a reunited stream.

5. Apparatus for continuously mixing plastic material including a housing for laterally conning the ow of a stream of plastic material therethrough, a rst distributing member for dividing the stream along a first line through approximately its center into two substantially equal parts, distributing surfaces angularly disposed to each other and to the direction of flow of the stream for directing outwardly the parts of said stream from said first dividing line, a plurality of channels extending through said distributing member from said surfaces for directing material from one side of the dividing line to the other into a reunited stream in the housing, a second distributing member for redividing the stream along a second line through approximately the center of said reunited stream into substantially equal parts, said first and second dividing lines being at approximately right angles to the stream and to each other, distributing surfaces angularly disposed to each other and to the direction of flow of the strea'rn for directing outwardly the parts of said stream from said second dividingI line, and a plurality of channels extending through said second distributing member from the distributing surfaces thereof for directing material from each part of the redivided stream from one side of the second dividing line to the other into a reunited stream.

JAMES BAILEY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 161,708 Schafhaus Apr. 6, 1875 1,626,487 Warren Apr. 26, 1927 2,284,255 Baureschmidt May 26, 1942 FOREIGN PATENTS Number Country Date 209,826 Germany June 4, 1907 735,033 France Nov. 2, 1932 

